dropdown_timers=[];
close_trashhold=200
function hide_submenu(menu_id){
    dropdown_timers[menu_id]=setTimeout('dropdown_close('+menu_id+')',close_trashhold);
}

function togle_submenu(menu_id){
    if (dropdown_timers[menu_id]){
        clearTimeout(dropdown_timers[menu_id]);
    } else {
        document.getElementById('submenu_'+menu_id).style.display="block";
    }
}

function dropdown_close(menu_id){
    document.getElementById('submenu_'+menu_id).style.display="none";
    dropdown_timers[menu_id]=null;
}